Electric current from Schwinger’s time-ordered propagator

Authors

  • C. Villavicencio Departamento de Ciencias Básicas, Universidad del Bio Bio

DOI:

https://doi.org/10.31349/RevMexFis.72.010801

Keywords:

Schwinger’s proper-time method; external electromagnetic field; electric conductivity

Abstract

The quasistatic electric current density of fermions in the presence of an external electric field is determined through the utilization of a time-ordered Schwinger propagator. The study encompasses the necessary conditions for establishing a well-defined time-ordered propagator within the Schwinger formalism, specifically concentrating on constant and uniform electromagnetic fields. Within this theoretical framework, a chemical potential is introduced, resulting in non-zero values for the electric current and charge number density. Consequently, the dependence of electric conductivity on the strength of the electric field and the charge number density is investigated.

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Published

2026-01-01

How to Cite

[1]
C. Villavicencio, “Electric current from Schwinger’s time-ordered propagator”, Rev. Mex. Fís., vol. 72, no. 1 Jan-Feb, pp. 010801 1–, Jan. 2026.

Issue

Vol. 72 No. 1 Jan-Feb (2026): Revista Mexicana de Física

Section

08 High Energy Physics

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Copyright (c) 2026 C. Villavicencio

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